1 #ifndef MSP_GL_BUFFERABLE_H_
2 #define MSP_GL_BUFFERABLE_H_
10 Base class for things that can store data in buffers. Supports buffer sharing.
11 A dirty flag is provided for derived classes. It should be set when the data
12 in the buffer is considered out of date, and is cleared by Bufferable after
13 uploading fresh data to the buffer.
21 const Bufferable &bufferable;
25 AsyncUpdater(const Bufferable &);
34 Bufferable *next_in_buffer;
35 Bufferable *prev_in_buffer;
36 mutable bool location_dirty;
42 virtual ~Bufferable();
44 /** Sets the buffer to use. If prev is not null, it must use the same
45 buffer, and this object is inserted after it. */
46 void use_buffer(Buffer *buf, Bufferable *prev = 0);
48 /** Sets the buffer for the entire chain of objects. */
49 void change_buffer(Buffer *);
51 /** Returns the total amount of storage required by this object and others
52 in the same chain, including any alignment between objects. */
53 unsigned get_required_buffer_size() const;
55 /** Uploads new data into the buffer if necessary. */
56 void refresh() const { if(buffer && dirty) upload_data(0); }
58 /** Returns an object which can be used to upload data to the buffer using
60 AsyncUpdater *refresh_async() const;
63 void unlink_from_buffer();
66 /** Returns the buffer in which the data is stored. */
67 const Buffer *get_buffer() const { return buffer; }
69 /** Returns the size of the data, in bytes. */
70 virtual unsigned get_data_size() const = 0;
73 /** Returns a pointer to the start of data in client memory. */
74 virtual const void *get_data_pointer() const = 0;
76 /** Returns the alignment required for the data, in bytes. The offset is
77 guaranteed to be a multiple of this. */
78 virtual unsigned get_alignment() const { return 1; }
80 /** Updates the offsets for the chain so that data from different objects
81 does not overlap. Should be called if either data size or alignment
86 /** Returns the offset of the data from the beginning of the buffer. */
87 unsigned get_offset() const { return offset; }
90 /** Called when the target buffer or offset within it has changed. */
91 virtual void location_changed(Buffer *, unsigned, unsigned) const { }
93 /** Uploads data to the buffer. Receives pointer to mapped buffer memory as
94 parameter, or null to use the buffer upload interface. */
95 void upload_data(char *) const;